Publication highlights

The brain’s neocortex contains both excitatory and inhibitory neurons, with inhibitory neurons thought to regulate and coordinate the activity of excitatory cells. Inhibitory neurons were thought to make dense non-specific connections with nearby excitatory cells.

However, researchers at the Francis Crick Institute as well as at the Sainsbury Wellcome Centre at UCL and the Biozentrum at the University of Basel have found that parvalbumin-positive (PV+) neurons, a major subtype of inhibitory cells, strongly inhibit a subset of nearby excitatory cells that provide them with strong excitatory inputs. By characterizing the response properties of PV+ neurons in the visual cortex and measuring the strength of their connections, they found that PV+ specifically made strong connections to those excitatory cells that had similar visual responses. This may play an important role in maintaining stable network activity and preventing uncontrolled firing of excitatory neurons.